Semiconductor device having IGBT and diode

Abstract

A semiconductor device includes: a semiconductor substrate; a IGBT region including a first region on a first surface of the substrate and providing a channel-forming region and a second region on a second surface of the substrate and providing a collector; a diode region including a third region on the first surface and providing an anode or a cathode and a fourth region on the second surface and providing the anode or the cathode; a periphery region including a fifth region on the first surface and a sixth region on the second surface. The first, third and fifth regions are commonly and electrically coupled, and the second, fourth and sixth regions are commonly and electrically coupled with one another.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:

FIGS. 1A and 1B are cross sectional views showing semiconductor devices according to example embodiments of the present disclosure;

FIGS. 2A and 2B are cross sectional views showing semiconductor devices according to other example embodiments of the present disclosure;

FIG. 3 is a cross sectional view showing a semiconductor device according to another example embodiment of the present disclosure;

FIGS. 4A and 4B are cross sectional views showing semiconductor devices according to other example embodiments of the present disclosure;

FIG. 5 is a cross sectional view showing a semiconductor device according to further another example embodiment of the present disclosure;

FIG. 6 is a bottom view showing a semiconductor device according to another example embodiment of the present disclosure;

FIG. 7 is a perspective view showing a semiconductor device according to a prior art;

FIG. 8 is an equivalent circuit diagram showing the device in FIG. 7;

FIG. 9A is a circuit diagram showing an evaluation circuit for measuring a current waveform in the device, and FIG. 9B is an example graph showing a current waveform in the device;

FIGS. 10A-10D are cross sectional views showing semiconductor devices according to other example embodiments of the present disclosure;

FIG. 11A is a top view and FIG. 11B is a bottom view showing a semiconductor device according to another example embodiment of the present disclosure,

FIG. 12A is a top view and FIG. 12B is a bottom view showing a semiconductor device according to another example embodiment of the present disclosure,

FIG. 13A is a top view and FIG. 13B is a bottom view showing a semiconductor device according to another example embodiment of the present disclosure, and

FIG. 14A is a top view and FIG. 14B is a bottom view showing a semiconductor device according to another example embodiment of the present disclosure.

Claims

1. A semiconductor device comprising: a semiconductor substrate having a first conductive type and first and second surfaces;an IGBT region having an IGBT and disposed in the substrate;a diode region having a diode and disposed in the substrate; anda periphery region disposed in the substrate, whereinthe IGBT region includes: a first semiconductor region having a second conductive type and disposed in a surface portion of the first surface of the substrate, the first semiconductor region providing a channel-forming region of the IGBT; anda second semiconductor region having the second conductive type and disposed in a surface portion of the second surface of the substrate, the second semiconductor region facing the first semiconductor region and providing a collector of the IGBT,the diode region includes: a third semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate, the third semiconductor region providing one of an anode and a cathode of the diode; anda fourth semiconductor region having the first conductive type and disposed in a surface portion of the second surface of the substrate, the fourth semiconductor region facing the first semiconductor region and providing the other one of the anode and the cathode of the diode,the periphery region includes: a fifth semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate; anda sixth semiconductor region having the second conductive type and disposed in a surface portion of the second surface of the substrate, the sixth semiconductor region facing the fifth semiconductor region,the first, third and fifth semiconductor regions are commonly and electrically coupled with one another, andthe second, fourth and sixth semiconductor regions are commonly and electrically coupled with one another.

2. The device according to claim 1, the first conductive type is a N conductive type, and the second conductive type is a P conductive type, andthe third semiconductor region provides the anode of the diode, andthe fourth semiconductor region provides the cathode of the diode.

3. The device according to claim 1, the first conductive type is a P conductive type, and the second conductive type is a N conductive type, andthe third semiconductor region provides the cathode of the diode, andthe fourth semiconductor region provides the anode of the diode.

4. The device according to claim 1, further comprising: a backside electrode disposed on the second surface of the substrate, whereinthe backside electrode is disposed in the periphery region, the diode region and the IGBT region so that the second, fourth and sixth semiconductor regions are commonly and electrically coupled with the backside electrode.

5. The device according to claim 1, further comprising: a seventh semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate, whereinthe seventh semiconductor region surrounds the first, third and fifth semiconductor regions,the fifth semiconductor region has one end near the seventh semiconductor region,the periphery region further includes an electrode disposed on the fifth semiconductor region,the electrode has one end near the seventh semiconductor region, anda distance between the one end of the fifth semiconductor region and the one end of the electrode is equal to or longer than a diffusion length of a hole in the substrate between the fifth semiconductor region and the sixth semiconductor region.

6. The device according to claim 1, the sixth semiconductor region is only disposed under the fifth semiconductor region.

7. The device according to claim 1, the sixth semiconductor region is disposed on a whole of the second surface of the substrate other than the surface portion of the second semiconductor region and the surface portion of the fourth semiconductor region.

8. The device according to claim 1, the IGBT region surrounds the diode region, andthe fifth semiconductor region in the periphery region surrounds the IGBT region.

9. The device according to claim 1, the fifth semiconductor region has an impurity concentration lower than an impurity concentration of the third semiconductor region.

10. The device according to claim 1, the fifth semiconductor region has a depth in a direction perpendicular to the first surface of the substrate, andthe depth of the fifth semiconductor region is shallower than a depth of the third semiconductor region.

11. The device according to claim 1, the fifth semiconductor region includes a plurality of diffusion regions, andadjacent two of the diffusion regions are partially overlapped each other so that the diffusion regions are connected together.

12. The device according to claim 1, the fifth semiconductor region includes an insulation film in a trench.

13. The device according to claim 1, the periphery region further includes a gate wiring for the IGBT, andthe gate wiring is disposed on the fifth semiconductor region with an insulation film between the gate wiring and the fifth semiconductor region.

14. The device according to claim 1, the periphery region further includes a pad electrode, andthe pad is disposed on the fifth semiconductor region with an insulation film between the pad electrode and the fifth semiconductor region.

15. A semiconductor device comprising: a semiconductor substrate having a first conductive type and first and second surfaces;an IGBT region having an IGBT and disposed in the substrate;a diode region having a diode and disposed in the substrate; anda periphery region disposed in the substrate, whereinthe IGBT region includes: a first semiconductor region having a second conductive type and disposed in a surface portion of the first surface of the substrate, the first semiconductor region providing a channel-forming region of the IGBT; anda second semiconductor region having the second conductive type and disposed in a surface portion of the second surface of the substrate, the second semiconductor region facing the first semiconductor region and providing a collector of the IGBT,the diode region includes: a third semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate, the third semiconductor region providing one of an anode and a cathode of the diode; anda fourth semiconductor region having the first conductive type and disposed in a surface portion of the second surface of the substrate, the fourth semiconductor region facing the first semiconductor region and providing the other one of the anode and the cathode of the diode,the periphery region includes a fifth semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate,the IGBT region is disposed between the periphery region and the diode region,the first, third and fifth semiconductor regions are commonly and electrically coupled with one another, andthe second and fourth semiconductor regions are commonly and electrically coupled with one another.

16. The device according to claim 15, the IGBT region surrounds the diode region, andthe fifth semiconductor region in the periphery region surrounds the IGBT region.

17. The device according to claim 16, the first conductive type is a N conductive type, and the second conductive type is a P conductive type, andthe third semiconductor region provides the anode of the diode, andthe fourth semiconductor region provides the cathode of the diode.

18. The device according to claim 16, the first conductive type is a P conductive type, and the second conductive type is a N conductive type, andthe third semiconductor region provides the cathode of the diode, andthe fourth semiconductor region provides the anode of the diode.

19. The device according to claim 16, further comprising: a seventh semiconductor region having the second conductive type and disposed in a surface portion of the first surface of the substrate, whereinthe seventh semiconductor region surrounds the first, third and fifth semiconductor regions,the fifth semiconductor region has one end near the seventh semiconductor region,the periphery region further includes an electrode disposed on the fifth semiconductor region,the electrode has one end near the seventh semiconductor region, anda distance between the one end of the fifth semiconductor region and the one end of the electrode is equal to or longer than a diffusion length of a hole in the substrate under the fifth semiconductor region.

20. The device according to claim 15, further comprising: a backside electrode disposed on the second surface of the substrate; andan insulation layer disposed on the second surface of the substrate, whereinthe backside electrode is disposed in the diode region and the IGBT region so that the second and fourth semiconductor regions are commonly and electrically coupled with each other, andthe insulation layer is disposed in the periphery region.

21. The device according to claim 15, further comprising: a backside electrode disposed on the second surface of the substrate, whereinthe backside electrode is disposed in the diode region and the IGBT region so that the second and fourth semiconductor regions are commonly and electrically coupled with each other, andthe backside electrode is not disposed in the periphery region.

22. The device according to claim 15, further comprising: a backside electrode disposed on the second surface of the substrate; anda high resistance layer disposed in the periphery region, whereinthe backside electrode is disposed in the periphery region, diode region and the IGBT region so that the second and fourth semiconductor regions are commonly and electrically coupled with each other, andthe high resistance layer is disposed between the substrate and the backside electrode.

23. The device according to claim 15, the fifth semiconductor region has an impurity concentration lower than an impurity concentration of the third semiconductor region.

24. The device according to claim 15, the fifth semiconductor region has a depth in a direction perpendicular to the first surface of the substrate, andthe depth of the fifth semiconductor region is shallower than a depth of the third semiconductor region.

25. The device according to claim 15, the fifth semiconductor region includes a plurality of diffusion regions, andadjacent two of the diffusion regions are partially overlapped each other so that the diffusion regions are connected together.

26. The device according to claim 15, the fifth semiconductor region includes an insulation film in a trench.

27. The device according to claim 15, the periphery region further includes a gate wiring for the IGBT, andthe gate wiring is disposed on the fifth semiconductor region with an insulation film between the gate wiring and the fifth semiconductor region.

28. The device according to claim 15, the periphery region further includes a pad electrode, andthe pad is disposed on the fifth semiconductor region with an insulation film between the pad electrode and the fifth semiconductor region.